Open the Photos app
Find and tap the picture
Tap the info button or swipe up on the photo
Look for visual lookup suggestions
Tap the detected object, landmark, plant, or animal if available
Use Safari or Google app for reverse image search
Open Google Images in Safari
Tap the aA or share button if needed to upload the image
Select the photo from your library
Search using the uploaded image
Use the Google app camera icon for Lens
Tap the Lens icon
Choose a photo from your iPhone
Review the search results
Use the Files app if the picture is stored there
Open the image and share it to a search app if supported